The Main Library is a historic library on the campus of the University of Illinois Urbana-Champaign in Urbana, Illinois. Built in 1924, the library was the third built for the school; it replaced Altgeld Hall, which had become too small for the university's collections. Architect Charles A. Platt designed the Georgian Revival building, one of several on the campus which he designed in the style. The building houses several area libraries, as well as the University Archives and the Rare Book & Manuscript Library. The Main Library is the symbolic face of the University Library, which has the second largest university library collection in the United States.